Time-Trend Analysis of Low Birthweight in Greece: Mapping a Heavy Public Health Burden.

Introduction: Low birthweight is a critical determinant of neonatal and infant mortality and is further associated with several long-term adverse health outcomes. This study aims to comprehensively analyze low birthweight rate (LBWR) trends in Greece from 1980 to 2023.

Materials and methods: National official data on live births in Greece from 1980 to 2023 were obtained from the Hellenic Statistical Authority, based on birth certificate records. A total of 4,593,229 live births were analyzed and categorized by birthweight. The annual LBWR (birthweight < 2,500 g) and very low birthweight rate (VLBWR) (birthweight < 1,500 g) were calculated per 100 total live births. Additionally, the annual moderately low birthweight rate (MLBWR) was computed separately for two subgroups: 1,500-1,999 g and 2,000-2,499 g. Time trends for these rates were evaluated using joinpoint regression analysis, and the annual percent change (APC) was calculated with 95% confidence intervals (95% CI).

Results: After a decade of stability from 1980 to 1990, the LBWR in Greece entered a 20-year period of consistent increase (1990-2010), with an APC of 2.3 (95% CI: 1.9 to 4.9). In the most recent period (2010-2023), the LBWR has plateaued at high levels. The LBWR reached its lowest point in 1982 at 5.58% and increased by 80%, reaching historically high levels in 2022 and 2023 at 10.07% and 10.02%, respectively. Since 2008, it has consistently remained above 9%. The VLBWR exhibited a steady upward trend throughout the entire 1980-2023 period with an APC of 0.9 (95% CI: 0.7 to 1.1) and increased from a low of 0.70% in 1980 to a peak of 1.20% in 2010. For the 2,000-2,499 g category, the MLBWR rose steadily over three decades (1980-2010: APC = 2.0, 95% CI: 1.8 to 2.3) and remained essentially unchanged from 2010 to 2023. In contrast, the MLBWR for the 1,500-1,999 g group showed a non-significant trend during 1980-1990, followed by a rapid increase between 1990 and 2001 (APC = 3.9, 95% CI: 2.9 to 7.9), which continued at a slower pace from 2001 to 2023 (APC = 1.0, 95% CI: 0.5 to 1.3).

Conclusions: During 1980-2023, the LBWR increased by 80%, with significant rising trends in the 1990s and 2000s, resulting in Greece having the highest rates among high-income countries. Whereas the overall LBWR has stabilized since 2010, there has been a continued rise in the proportion of neonates with birthweight < 2,000 g, who face the highest risk of adverse outcomes. Continued monitoring of LBWR is essential, alongside investments in the implementation of effective, targeted interventions.